I am very confused by these, and even when I understand other people's usage of them I find it difficult to know when to employ them myself. For this reason, I am trying to make my own examples and see if I get them correct. Please understand, English is not my first language, but I have never learned grammar in my native language either. I hope that what I'm saying is comprehensible to you.

In the following examples, I'll be using a period in place of the em dash or semicolon, because I am utterly confused as to which one should be used.

English is not my first language, and I'm having trouble with the grammar. Specifically semicolons and dashes.

Don't ask Jim to fix your car. That sort of thing would be better handled by Steve.

The question isn't what you can take away from this, but what you can learn in the process. / The question isn't what you can take away from this. It is what you can learn in the process.

Normally I would use a semicolon in all of these instances, but recently I have come to learn that this is incorrect usage.

I'd only change the first example (though a dash in the second would be fine): English is not my first language, and I'm having trouble with the grammar – specifically, with the use of semicolons and dashes.
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Edwin AshworthJan 26 '13 at 23:45

8 Answers
8

Dashes can be used in place of parentheses to indicate an aside or qualifying statement. I don't think either has a place in any of your examples.

Generally speaking, for the same reason you're having a hard time understanding their use, it's a good idea to avoid using semicolons altogether. The semicolon is intended to separate two sentences where the second sentence clarifies or extends the first. In practice, they're often used incorrectly and there is ample evidence that they confuse readers and translation software. A comma or period would often suffice.

It's good advice to use the simplest punctuation possible. That often means using the simplest sentence construction possible as well. Here is how I would punctuate your examples:

English is not my first language. I'm having trouble understanding the punctuation, specifically semicolons and dashes.

Note here that the wording is more specific so that the second clause merely clarifies. It could be thought of as a contraction of this more verbose version:

English is not my first language. I'm having trouble understanding the punctuation. Specifically, I'm having trouble understanding semicolons and dashes.

Or, if you really felt the need to use that spare semicolon:

English is not my first language. I'm having trouble understanding the punctuation; specifically, I'm having trouble understanding semicolons and dashes.

Your second example is fine as is; it's completely clear in meaning as two sentences (see what I did there?).

Your third sentence provides a great example of the many ways to associate two sentences. The first is very clear, but awkward and wordy. The second is probably most confusing to readers because the second sentence is quasi-grammatical. "it" implies "The question" here. The third is a rather elegant construction to my native English comprehension. Does the conjunction "but" imply the same meaning to you, however?

The question isn't what you can take away from this. The question is what you can learn in the process.

The question isn't what you can take away from this; it is what you can learn in the process.

The question isn't what you can take away from this, but what you can learn in the process.

These all mean exactly the same thing. From your perspective, take the construction that makes the most sense and use that consistently in your writing. Much great writing can be done without any semicolons at all.

Finally, note that your last example is a rhetorically loaded construction in English. I'm sure "Not this, but that" phrasings are encountered in many languages. Here's a famous example:

Ask not what your country can do for you. Ask what you can do for your country.

In these cases, simple, repeated, parallel constructions work in your favor in spite of the punctuation:

It was the best of times, it was the worst of times, it was the age of wisdom, it was the age of foolishness...

Be clear. Be consistent. Remember that many writers don't actually know the rules of punctuation. My apologies for rambling.

I like the use of em-dash in nested appositives. Simple appositives only require commas. Edgar Allen Poe wrote a great piece on effective use of the em-dash. The semi-colon can indicate transition in some context or another-- feeling, position or contradiction. Sometimes I decide which to use based on either appositive effect or transition effect.

The dash – used sensitively – can add a dimension to the meaning of a sentence over and above the sum total of the weight of the words.
The order, the balance, the nature of the vocabulary used give dimension, too, but the nuances, the humour, the point, the comment implicit in a sentence can often be brought out by the careful use of the dash. It is a punctuation mark that is the more effective for being used sparingly: when it appears it needs to pack its own punch.

The question is not dash v semicolon: in the examples given a comma would be perfectly adequate.

English is not my first language and I'm having trouble with the grammar, specifically semicolons and dashes. (No comma needed after 'language'.)

Don't ask Jim to fix your car, that sort of thing would be better handled by Steve. (A dash would also work here.)

The question isn't what you can take away from this but what you can learn in the process. OR The question isn't what you can take
away from this. It is what you can learn in the process. (Both of
these work equally well but it's a question of style: the second
version is more emphatic. It would work well in a speech.)

You can get away with random dashes if writing informally but should use them sparingly and correctly in formal writing. That's a useful PPT link @Edwin has posted, to quote:

"It is not acceptable to use dashes in a slovenly manner to avoid
having to decide whether a full stop is required or not." (Not that you were doing this - but others do.)

This is best handled by the em dash. Although the second sentence does elucidate and qualify the first sentence, it reads, to me, like an interjection of sorts. The reason the colon does not work here is because the first sentence is not in dire need of elaboration. The second sentence is a helpful, "added thought" that seems most appropriately indicated with the em dash.

This is best handled by the colon. This is because the first sentence, in a loose sense, is not a completely explained idea. The second sentence is (in my opinion) a necessary elucidation and the colon, to me, indicates a strong qualifying clause to follow.

The colon is best used here as well for the same reasons as the second sentence. The first sentence is, in some way, incomplete without the elaboration in the second sentence.

In general, semicolons are losing their popularity; however, this is not to say they do not have their place.

To qualify a preceding clause: an appropriate use of the colon.

The em dash tends to address ideas that seem to come "ad-lib," or an interruption of thought--but they can be used, in an informal sense, in place of many punctuations with success.

Semicolons can often replace conjunctions which precede a result or reason, conjunctions such as "because", "since", "for", etc. For instance, "he went to the milk bar because he wanted some curly wurly bars" could have 'because' replaced with a semicolon: "he went to the milkbar; he wanted some curly wurly bars". Number 2 could have a semi-colon, but it's not necessary. Semi-colons can also juxtapose two different ideas. So 3 could have a semicolon as well.

I was taught in school that use of a semi-colon should only be where it could be substituted with a full-stop (period, in American English). It should (or rather, can) be used to indicate that the second part follows on from the first. So the first example should definitely not be a semi-colon, as the second part has no verb, and thus cannot form a sentence on it's own.

If I were writing this sentence, I would actually use a comma. I don't think it forms a sufficient break in the sentence to constitute an en-dash, and you may risk over-using the en-dash, which can make sentences appear stilted. I would also take out the first comma.

English is not my first language and I'm having trouble with the grammar, specifically semicolons and dashes.

Why not a colon as others have suggested? I tend to use the rule that colons should only be before a list, or as an augmented period to indicate that the second part defines or gives an example of the first.

So, by that logic, the second example should probably be either left as-is, or use a semi-colon:

Don't ask Jim to fix your car; that sort of thing would be better handled by Steve.

The first version of the third example is fine. The second version could optionally have a semi-colon too, as the part after the semi-colon follows on from the first:

The question isn't what you can take away from this; it is what you can learn in the process.

Generally, I would avoid using the en-dash unless you're sure that it is correct and clarifies to the reader, especially when writing formally. The most accepted formal use-case is probably in place of brackets (parentheses) to form an aside – but even then, if I had used an en-dash around the word "parentheses", it would have looked weird, so perhaps the rule there is to only use it where the aside is of sufficient length.